Decoder equipment generating an order for an audio profile that is to be applied

ABSTRACT

A decoder equipment includes a first output suitable for connecting to audio playback equipment; a second output suitable for connecting to video playback equipment; a communication interface arranged in service to receive both an incoming audio/video stream and also incoming metadata; processor means arranged: to process the incoming audio/video stream in order to supply an audio signal at least to the audio playback equipment and a video signal to the video playback equipment; to extract from the incoming metadata information about the incoming audio/video stream and consequently to generate an order for the audio playback equipment, the order specifying an audio profile that is to be applied as a function of said information.

The invention relates to the field of audio/video playback via one ormore pieces of playback equipment.

BACKGROUND OF THE INVENTION

Nowadays, in modern home multimedia installations, it is very frequentfor decoder equipment to be connected both to audio/video playbackequipment and also to one or more pieces of audio playback equipmentthat are distinct from the audio/video playback equipment, for thepurpose of improving a user's listening experience during playback ofaudio/video content.

Still for the purpose of improving the user's listening experience, itis possible to act on various parameters of the audio playbackequipment, e.g. by boosting its bass or by filtering certainfrequencies. The user can generally adjust these parameters either byacting directly on the audio playback equipment itself (by means of aknob, a dimmer, . . . ), or else by modifying parameters in aconfiguration menu projected by the audio/video playback equipment thatis associated with the audio playback equipment.

Nevertheless, that obliges the user to act personally to modify thevarious parameters, which can be found to be relatively tedious. Also,the user does not necessarily select the most appropriate parameters.

OBJECT OF THE INVENTION

An object of the invention is to propose decoder equipment that enablesthe user's listening experience to be improved even more.

SUMMARY OF THE INVENTION

In order to achieve this object, the invention provides decoderequipment comprising:

-   -   a first output suitable for connecting to audio playback        equipment;    -   a second output suitable for connecting to video playback        equipment;    -   a communication interface arranged in service to receive both an        incoming audio/video stream and also incoming metadata;    -   processor means arranged:        -   to process the incoming audio/video stream in order to            supply an audio signal at least to the audio playback            equipment and a video signal to the video playback            equipment;        -   to extract from the incoming metadata at least one            information about the incoming audio/video stream and            consequently to generate an order for the audio playback            equipment, the order specifying an audio profile that is to            be applied as a function of said information;

wherein the information is a time.

On the basis of the order sent, the audio playback equipment can act inservice to adapt the audio signal received from the decoder equipment.This serves to adapt at least one of the parameters of the audio signalplayed back by the audio playback equipment in response to theaudio/video stream input to the decoder equipment, thereby enabling theuser to benefit from a very good listening experience.

It should be understood that the decoder equipment supplies the audioplayback equipment both with the raw audio signal and also with an orderto adapt said raw signal, with the adaptation then taking place withinthe audio playback equipment.

This enables the adaptation to be more effective. In particular, thedecoder equipment may thus be equipment that is relatively simple(possibly even a smartphone) since it is the audio playback equipmentthat itself applies the processing to the audio signal in order tomodify it in response to the information extracted by the decoderequipment.

The information supplied is thus a time applicable either to a programcontained in the incoming audio/video stream that is being played backin service by the audio playback equipment and by the video playbackequipment, or else to a program that is going to be played backsubsequently in service by the audio playback equipment and by the videoplayback equipment.

Optionally, the processor means also extract from the incoming metadataother additional information which is a content type descriptor of theincoming audio/video stream.

Optionally, the processor means include at least one table associatingeach descriptor with parameters defining an audio profile, at least inpart.

Optionally, the processor means include at least one table associatingeach descriptor with an audio profile identifier.

Optionally, the information is an end time of a program contained in theincoming audio/video stream and played back in service by the audioplayback equipment and by the video playback equipment.

Optionally, the processor means also extract, from the incomingmetadata, additional information comprising an end time of a programthat is contained in the incoming audio/video stream and that is goingto be played back in service by the audio playback equipment and by thevideo playback equipment after the program currently being played backby the audio playback equipment and by the video playback equipment.

Optionally, the decoder equipment is configured to cause an audioprofile change to coincide with a program change.

Optionally, the audio profile is also a function of the time at whichthe audio/video stream is played back.

Optionally, the decoder equipment is configured to calculate atransition period between two audio profiles.

Optionally, the decoder equipment is configured to order the audioplayback equipment to calculate a transition period between two audioprofiles.

Optionally, the decoder equipment is configured to combine two audioprofiles.

Optionally, the decoder equipment is configured to order the audioplayback equipment to combine two audio profiles.

Optionally, the audio profile is defined at least by a parameter forequalizing the audio signal.

The audio profile thus contains information about equalizing the audiosignal.

Optionally, the audio profile is defined at least by a compressor orlimiter effect.

By way of example, the audio profile thus contains information aboutcompressing the dynamic range of the sound.

Optionally, the transition between two profiles is caused by a change oftime at which the audio/video stream is played back and/or a change ofprogram contained in the incoming audio/video stream that is played backin service by the audio playback equipment and by the video playbackequipment.

The transition between profiles thus takes place during a change ofprogram and/or during a change of time (e.g. changing to a “night”profile).

The invention also provides audio playback equipment including acommunication interface arranged in service to receive from decoderequipment both an audio signal and also an order for an audio profilethat is to be applied, the audio playback equipment including processormeans for adapting the audio signal as a function of said order.

Optionally, the processor means include at least one table associatingaudio profile identifiers with parameters defining an audio profile, atleast in part.

Optionally, the audio playback equipment is configured to change audioprofile at any given time specified by the decoder equipment.

Optionally, the audio playback equipment is configured to ensure atransition period between two audio profiles.

Optionally, the audio playback equipment is configured to combine twoaudio profiles.

Optionally, for at least one audio parameter, the audio playbackequipment duplicates the audio signal it receives in service from thedecoder equipment, applies respective audio parameters to each copy, andcombines the two copies in order to obtain a combined audio signal.

Optionally, for at least one audio parameter, in service, the audioplayback equipment applies a combined audio parameter directly to theaudio signal received from the decoder equipment.

The invention also provides an installation comprising decoder equipmentas specified above associated with audio playback equipment as specifiedabove.

The invention also provides a method of generating an order for an audioprofile that is to be applied by audio playback equipment, the methodbeing performed by decoder equipment as specified above.

The invention also provides a method of applying an audio profile, whichmethod is performed by the audio playback equipment as specified above.

The invention also provides a computer program including instructionsfor causing the audio playback equipment as specified above to executethe steps of the method as specified above.

The invention also provides a computer program including instructionsfor causing the installation as specified above to execute the steps ofthe method as specified above.

The invention also provides a computer readable storage medium havingeither of the above-mentioned computer programs stored thereon

Other characteristics and advantages of the invention appear on readingthe following description of a particular, nonlimiting embodiment of theinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention can be better understood in the light of the followingdescription given with reference to the accompanying figures, in which:

FIG. 1 shows an installation in a particular embodiment of theinvention;

FIG. 2 is a table showing examples of content type descriptors passingthrough the installation shown in FIG. 1;

FIG. 3a is a table giving examples of audio profiles associated with thecontent type descriptors shown in FIG. 2;

FIG. 3b shows a first example of an order for an audio profile that isto be applied as generated from the table shown in FIG. 3 a;

FIG. 3c shows a second example of an order for an audio profile that isto be applied as generated from the table shown in FIG. 3 a;

FIG. 4a is a table giving examples of audio profile identifiersassociated with the content type descriptors shown in FIG. 2;

FIG. 4b is a table giving examples of audio profiles associated with theaudio profile identifiers shown in FIG. 4 a;

FIG. 4c shows a third example of an order for an audio profile that isto be applied as generated from the table shown in FIG. 4 a;

FIG. 5 shows a fourth example of an order for an audio profile that isto be applied passing through the installation shown in FIG. 1;

FIG. 6 is a flowchart illustrating a first possibility for the deviceshown in FIG. 1 to adapt an audio signal as a function of the time andof information extracted from metadata;

FIG. 7 is a flowchart illustrating a second possibility for the deviceshown in FIG. 1 to adapt an audio signal as a function of the time andof information extracted from metadata;

FIG. 8 shows a fifth example of an order for an audio profile that is tobe applied passing through the installation shown in FIG. 1;

FIG. 9 is a diagram showing a first variant of two sets of audioparameters being combined by the installation shown in FIG. 1;

FIG. 10 is a diagram showing a second variant of two sets of audioparameters being combined by the installation shown in FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

With reference to FIG. 1, the installation in a particular embodiment isa multimedia installation comprising decoder equipment 11 that isconnected in this example to video playback equipment, and in reality inthis example both to a piece of audio/video playback equipment 13, andalso to a piece of audio playback equipment 15. The piece of audioplayback equipment 15 is not included in the decoder equipment 11: theyform two distinct entities that are in wired or wireless communication.

In this example, the decoder equipment 11 is a set-top box, the piece ofaudio/video playback equipment 13 is a television set, and the piece ofaudio playback equipment 15 is an external loudspeaker.

The audio/video playback equipment 13 is connected to an audio/videooutput of the decoder equipment 11. The audio playback equipment 15 isconnected to an audio output of the decoder equipment 11.

The decoder equipment 11 includes processor means serving, amongst otherthings, to process the incoming audio/video stream.

Thus, the term “audio/video output” is used to mean output on which thedecoder equipment 11 applies an audio/video signal in order to performboth audio playback and video playback via (at least) one piece ofaudio/video playback equipment 13 (specifically the television set). Theterm “audio output” is used to mean output on which the decoderequipment 11 applies an audio signal in order to perform audio playbackvia (at least) one piece of audio playback equipment 15 (specificallythe external loudspeaker).

In corresponding manner, the audio playback equipment 15 includesprocessor means specific thereto for processing the audio signal sent bythe decoder equipment, which signal is received via a communicationinterface of the audio playback equipment 15.

The main audio/video link 14 between the decoder equipment 11 and theaudio/video playback equipment, and the secondary audio link 16 betweenthe decoder equipment 11 and the audio playback equipment 15, are bothlinks that may be wired or wireless. Any type of technology may be usedfor providing these links: optical, radio, etc. The links may thus be ofdifferent “physical” natures (e.g. HDMI, Toslink, RCA, etc.) and/or theymay use different “computer” protocols (e.g. Bluetooth, UPnP, Airplay,Chromecast, etc.).

Thus, and in accordance with a nonlimiting option, the audio/videoplayback equipment 13 has an HDMI connection with the decoder equipment11, and the audio playback equipment 15 is connected via a localnetwork. By way of example, the local network may be a wireless networkof the Wi-Fi type, or it may be a wired network of the Ethernet type. Ina variant, the local network includes a Wi-Fi router, the decoderequipment 11 is connected to said Wi-Fi router by an Ethernet type wiredconnection, and the Wi-Fi router is connected to the audio playbackequipment via a wireless connection of Wi-Fi type.

From a communication interface of the decoder equipment 11, the decoderequipment 11 acquires an incoming multimedia stream, which stream maycome from one or more broadcast networks 12. The broadcast networks 12may be of any type. Thus, in a first embodiment, the broadcast network12 is a satellite television network, and the decoder equipment 11receives the incoming multimedia stream via a parabolic antenna. In asecond embodiment, the broadcast network 12 is an Internet connection,and the decoder equipment 11 receives the incoming multimedia stream viasaid Internet connection. In a third embodiment, the broadcast network12 is a digital terrestrial television (DTT) network or a cabletelevision network. Overall, the broadcast network 12 may be a varietyof sources: satellite, cable, IP, DTT, a locally stored video stream,etc.

In particular manner, the incoming multimedia stream received by thedecoder equipment 11 includes metadata together with an incomingaudio/video stream that has both an audio portion and a video portionthat are synchronized with each other.

The metadata contains information about said incoming audio/videostream. By way of example, the metadata may be in the DVB-SI format.This type of format is described in particular in the standard ETSI EN300 468 “Digital Video Broadcasting Specification for ServiceInformation in DVB systems”. The metadata may equally well be includedin a media presentation description (MPD) manifest, or it may be of anyother type. The type of metadata is likely to depend on the broadcastnetwork 12 in communication with the decoder equipment 11.

In this example, the processor means of the decoder equipment serve alsoto extract at least some of the information about the incomingaudio/video stream from the metadata. In a first option, the informationextracted from the metadata is a descriptor of the content type of theincoming audio/video stream, i.e. the program that is to be played backby the various pieces of playback equipment. If the metadata is in theabove-described DVB-SI format, it includes a content type descriptor asspecified in paragraph 6.2.9 of the ETSI EN 300468 standard, and thedecoder equipment 11 thus extracts said descriptor. The ETSI EN 300 468standard gives examples of content type descriptors in its table 28.

The table shown in FIG. 2 gives a few examples of content typedescriptors for an incoming audio/video stream: thriller, comedy,romance, news, documentary, game show, variety show, sports (general),football/soccer, motor sport, children's programs, classical music,rock, ballet, etc. The content type descriptor thus describes thecategory of the program viewed on the audio/video playback equipment.

In this example, the content type descriptor is a string of alphanumericcharacters, for example a name.

On the basis of the content type descriptor, the decoder equipment 11generates an order for an audio profile that is to be applied by theaudio playback equipment 15, which audio profile is thus a function ofsaid content type. The decoder equipment 11 is thus adapted to controlthe audio playback equipment 15 so as to cause it to apply differentaudio profiles.

By way of example, the orders may be sent from the decoder equipment 11to the audio playback equipment 15 using a control protocol such as theJSON-RPC protocol (for more information, reference may be made to thesite https://www.jsonrpc.org), or else the CORBA protocol (for moreinformation, reference may be made to the linkhttps://fr.wikipedia.org/wiki/Common_Object_Request_Broker_Architecture).

An audio profile is defined by a set of parameters that affect the waysound is played back by the audio playback equipment 15. By way ofexample, an audio profile may be defined at least in part by anequalization curve that defines the gain that is to be applied as afunction of frequency in order to emphasize or attenuate bass, mid, ortreble bands. An audio profile may also be defined at least in part byone or more filters that are to be activated or deactivated, e.g. suchas a reverberation filter or a background noise attenuation filter. Whenthe audio profile is defined by at least one filter that is to beactivated, it may also be defined by at least one specific parameterthat is to be applied to said filter.

In nonlimiting manner, the parameters serving to define an audio profilemay be a bass gain value to be applied, a mid gain value to be applied,a treble gain value to be applied, reverberation filter on or off, thesound level of said filter, the application duration of said filter, . .. .

In order to generate the orders for audio profiles that are to beapplied, the decoder equipment 11 includes a table that enables theaudio profile that is to be applied to be identified for each contenttype descriptor.

In a first a variant, this table gives each content type descriptor adefinition for at least some of the parameters constituting thecorresponding audio profile and preferably for all of said parameters.FIG. 3a shows an example of such a table. Each content type descriptor(thriller, news, classical music, . . . ) is associated with the set ofparameters for the corresponding audio profile (a bass gain value to beapplied, a mid gain value to be applied, a treble gain value to beapplied, reverberation filter on or off, sound level of said filter, andapplication duration of said filter, . . . ).

In service, the decoder equipment 11 receives the incoming multimediastream and decodes it in order to extract both the audio/video streamand also the metadata.

As above, the decoder equipment 11 extracts, from said audio/videostream, both a video signal for the audio/video playback equipment 13,and also an audio signal for the audio playback equipment 15, andpossibly for built-in loudspeakers of the audio/video playback equipment13.

Furthermore, from the metadata, the decoder equipment 11 extracts atleast the content type descriptor of the audio/video stream, and fromits table it deduces the set of parameters that make up thecorresponding audio profile. The decoder equipment 11 thus supplies anorder to the audio playback equipment 15 for an audio profile that is tobe applied, which order in this example is in the form of the set ofparameters that are to be applied in order to generate the profile.FIGS. 3b and 3c give examples of orders sent by the decoder equipment 11to the audio playback equipment 15 (by way of nonlimiting example, theorders are shown written using the JSON-RPC protocol).

The audio playback equipment 15 thus recovers both the audio signal andthe order, and consequently the processor means of said audio playbackequipment 15 modify the audio signal by applying thereto the parameterscontained in the order. The audio signal applied by the audio playbackequipment 15 is thus a function of the program being viewed on theaudio/video playback equipment 13.

It can thus be seen that the decoder equipment 11 does not itself adaptthe audio/video stream, and the only processing it performs on theaudio/video stream serves to provide both an audio signal on at leastthe output terminal linked to the audio playback equipment 15, and alsoa video signal on the output terminal linked to the audio/video playbackequipment 13. In the invention, it is indeed the audio playbackequipment 15 that itself modifies the audio signal sent by the decoderequipment 11 in order to adapt it.

It should also be observed that the order sent by the decoder equipment11 is not the content type descriptor, but directly the parameters formodifying the playback of the sound. The type of content viewed on theaudio/video playback equipment 13 is indeed determined by the decoderequipment 11 and not by the audio playback equipment 15.

In a second variant, for each content type descriptor, this tabledefines an identifier of the corresponding audio profile. FIG. 4a showsan example of such a table. Each content type descriptor (thriller,news, classical music, motor sport, . . . ) is associated with anidentifier of the corresponding audio profile (spectacular, voice,hi-fi, spectacular, . . . ). The identifier of the audio profile thusdescribes the effect of the looked-for audio profile. An audio profileidentifier is thus not a content type descriptor.

In this example, an audio profile identifier is a string of alphanumericcharacters, for example a name.

In corresponding manner, the audio playback equipment 15 includes atable associating each audio profile identifier with a definition of atleast some of the parameters making up the corresponding audio profile,and preferably of all of said parameters. FIG. 4b shows an example of atable. Each audio profile identifier (spectacular, voice, hi-fi, . . . )is associated with the set of parameters of the corresponding audioprofile (a bass gain value to be applied, a mid gain value to beapplied, a treble gain value to be applied, reverberation filter on oroff, sound level of said filter, and application duration of saidfilter, . . . ).

In service, the decoder equipment 11 receives the incoming multimediastream and decodes it in order to extract both the audio/video streamand also the metadata.

As above, the decoder equipment 11 extracts, from said audio/videostream, both a video signal for the audio/video playback equipment 13,and also an audio signal for the audio playback equipment 15, andpossibly for built-in loudspeakers of the audio/video playback equipment13.

Furthermore, the decoder equipment 11 extracts, from the metadata, atleast the content type descriptor of the audio/video stream, anddeduces, from its table, the identifier of the corresponding audioprofile.

Consequently, the decoder equipment 11 sends an order to the audioplayback equipment 15 for an audio profile that is to be applied, whichorder, in this example, is in the form of the identifier of saidprofile. FIG. 4c gives an example of an order sent by the decoderequipment 11 to the audio playback equipment 15 (by way of nonlimitingexample, the order is shown written using the JSON-RPC protocol).

The audio playback equipment 15 thus receives both the audio signal andthe corresponding order. The processor means of the audio playbackequipment 15 use the table contained therein to recover the set ofparameters that constitute the corresponding audio profile.Consequently, said processor means of the audio playback equipment 15modify the audio signal by applying said parameters.

It can thus be seen that the decoder equipment 11 does not itself adaptthe audio/video stream, and the only processing it performs on theaudio/video stream serves to provide both an audio signal on at leastthe output terminal linked to the audio playback equipment 15, and alsoa video signal on the output terminal linked to the audio/video playbackequipment 13. In the invention, it is indeed the audio playbackequipment 15 that itself modifies the audio signal sent by the decoderequipment 11 in order to adapt it.

It should also be observed that the order sent by the decoder equipment11 is not the content type descriptor but directly the identifier of theprofile that is to be applied. The type of content viewed on theaudio/video playback equipment 13 is indeed determined by the decoderequipment 11 and not by the audio playback equipment 15.

Two different pieces of audio playback equipment may have their owntables that are different, and consequently they can associate differentparameters with the same profile identifier coming from the decoderequipment 11: the second variant thus has the advantage of being able toadapt to the specific characteristics of the respective loudspeakers ofthe respective pieces of audio playback equipment.

A third variant combining the first variant and the second variant isalso applicable.

In this third variant, the decoder equipment 11 has a first table givingeach content type descriptor a definition of at least some of theparameters that constitute the corresponding audio profile (similar tothat shown in FIG. 3a ) and a second table giving each content typedescriptor an identifier of the corresponding audio profile (similar tothat shown in FIG. 4a ).

Correspondingly, the audio/video playback equipment 15 includes a thirdtable associating each audio profile identifier with a definition of atleast some of the parameters making up the corresponding audio profile(similar to that shown in FIG. 4b ).

In service, the decoder equipment 11 receives the incoming multimediastream and decodes it in order to extract both the audio/video streamand also the metadata.

As above, the decoder equipment 11 extracts, from said audio/videostream, both a video signal for the audio/video playback equipment 13,and also an audio signal for the audio playback equipment 15, andpossibly for built-in loudspeakers of the audio/video playback equipment13.

Furthermore, the decoder equipment 11 extracts, from the metadata, atleast one content type descriptor of the audio/video stream, anddeduces, from the first table, the corresponding audio profileparameters and, from the second table, the identifier of thecorresponding audio profile.

Consequently, the decoder equipment 11 sends an order to the audioplayback equipment 15 for an audio profile that is to be applied, whichorder, in this example, is in the form both of the identifier of saidprofile and also of the parameters present in the first table.

Starting from this order, if the audio playback equipment 15 does notrecognize the identifier sent by the decoder equipment 11, then theaudio playback equipment 15 makes use of the parameters present in theorder (coming from the first table) in order to adapt the audio signal(in similar manner to that described in the first variant).

In contrast, if the audio playback equipment 15 does recognize theidentifier sent by the decoder equipment 11, then:

-   -   in one particular embodiment, the audio playback equipment 15        ignores the parameters sent by the decoder equipment 11 and        makes use of the parameters coming from its own third table as        determined by the identifier (in similar manner to that        described in the second variant);    -   in another particular embodiment, the audio playback equipment        15 makes use of the parameters sent by the decoder equipment 11,        and if any parameters are missing, it fills in with the values        contained in its own third table;    -   in yet another particular embodiment, the audio playback        equipment 15 combines the parameters sent by the decoder        equipment 11 with the parameters contained in its own third        table and then applies the combined parameters. The manner in        which the audio playback equipment 15 can make such a        combination is described below in the present application.

This third variant makes it possible to manage potential alterations toan installation by enabling a version of the audio playback equipment 15that is more recent than the decoder equipment 11 to have new parametersavailable in association with an audio profile and to be able to applythem, even though the older decoder element 11 has no knowledge of thenew parameters. Also, this third variant makes it possible to givepriority to the data of the decoder equipment 11 (data that may bepersonalized by the user, e.g. via a configuration menu displayed on theaudio/video playback equipment 13).

FIG. 5 gives an example of an order sent by the decoder equipment 11 tothe audio playback equipment 15 (by way of nonlimiting example, thisorder is written using the JSON-RPC protocol), the order containing bothan audio profile identifier and also parameters. On receiving thisorder, if the audio playback equipment 15 recognizes the identifier, itdetermines from its own third table whether there are any parametersother than those sent by the decoder equipment 11 and corresponding tothe identifier that are to be applied in order to be added to the datasent by the order.

The above description relates to a first option for an installation anda method enabling the audio signal that is played back by the audioplayback equipment to be adapted to the type of program being viewed onthe audio/video playback equipment.

In a second option, the installation is configured to adapt the audiosignal that is played back by the audio playback equipment 15 as afunction of time.

For this purpose, the decoder equipment 11 includes a clock and itgenerates an audio profile order as a function of time. Thus, by way ofexample, it may order a “normal” profile during the day and a “night”profile in the evening and at night. By way of example, the “night”profile may include parameters such as attenuating bass frequencies (itbeing known specifically that bass frequencies carry farther and aretherefore a greater nuisance for neighbors). Alternatively, or inaddition, the “night” profile may lower the volume overall whileselecting equalization parameters in which bass and treble attenuationis less than mid attenuation, since this is known to give the listenerthe impression that the volume is higher than it really is (inparticular, this effect used to be referred to as “loudness” on oldhi-fi systems). Alternatively, or in addition, the “night” profile mayactivate a “compressor” or “limiter” effect (for more information,reference may be made to the following articlehttps://fr.wikipedia.org/wiki/Compresseur_%28audio%29) that decreasesthe volume of noisy sequences while preserving the volume of quietersequences, and as a result the noisiest sequences (such as explosions ina film) are attenuated, while quieter sequences remain audible.

By way of example, the decoder equipment 11 includes a table giving eachtimeslot a definition of at least some of the parameters (bass gain, midgain, . . . ) and preferably all of the parameters defining audioprofiles and/or a table giving each timeslot an audio profile identifier(“night”, “day”, . . . ), and the audio playback equipment 15 thenincludes a table associating said identifiers with at least some of theparameters constituting the corresponding audio profile, and preferablywith all of the parameters. Operation is then similar to that of thefirst option concerning the three variants that are described for thefirst option.

Furthermore, in order to generate the order, the decoder equipment 11combines the time scheduled for changing the audio profile with at leastsome of the information extracted from the metadata other than thecontent type descriptor of the audio/video stream.

Typically, the decoder equipment 11 extracts, from the metadata, amarker of the audio/video stream that is being transcribed by theaudio/video equipment 13 (i.e. the program that is being played),information about the time the program is to end, and information aboutthe time the following program is to end. If the metadata is in theDVB-SI format as described in section 5.2.4 of the ETSI EN 300 468standard, the decoder equipment 11 thus extracts from the metadata themarker of the program being transcribed, the metadata being in the formof “event id” and the information “start time” and “duration” enablingthe decoder equipment 11 to calculate the end time of the program beingplayed and the end time of the following program.

Combining the time scheduled for the change of audio profile at leastwith the end time of the program being viewed serves to minimize anyinconvenience for the user while the audio profile is being changed,e.g. by shifting the instant at which the audio profile is changed so asto make it coincide with a change of program.

With reference to FIG. 6, there follows a description of a method inaccordance with a first possibility that enables the time scheduled forchanging the audio profile to be combined with the end times of thecurrent program and of the next program.

If the forecast time for the change of profile is close to a change ofprogram, then this method provides for the decoder equipment 11 to applythe change of profile at the moment the program changes. Advantageously,if the forecast time for the change of profile is remote from any changeof program, then the decoder equipment 11 applies the change of profileat the forecast time while ensuring that the transition between the oldprofile and the new profile is smooth.

In a step 601, the decoder equipment 11 determines the time t_(p)forecast for the next change of profile.

In a step 602, the decoder equipment 11 determines the end time t_(e) ofthe current program from the incoming metadata.

In a step 603, the decoder equipment 11 compares the time t_(p) forecastfor the next change of profile with the end time t_(e) of the currentprogram. If the time t_(p) forecast for the next change of profile isearlier than the end time t_(e) of the current program, then the decoderequipment 11 continues with a step 604, otherwise the decoder equipment11 continues with a step 609.

In step 604, the decoder equipment 11 compares the time t_(p) forecastfor the next change of profile with the end time t_(e) of the currentprogram as reduced by subtracting a fixed time interval Δ. If the timet_(p) forecast for the change of profile is earlier than the reduced endtime t_(e)−Δ of the current program, then the decoder equipment 11continues with a step 605, otherwise the decoder equipment 11 continueswith a step 607. By way of example, Δ may be selected to be equal to 5minutes.

In step 605, the decoder equipment 11 waits for the time t_(p) forecastfor the next change of profile, and then in a step 606, the decoderequipment 11 sends the external equipment 15 at least an order for a newaudio profile that is to be applied, thereby causing a smooth transitionto take place between the old audio profile and the new audio profile.The way in which the installation can perform a smooth transition isexplained below in the present application.

In step 607, the decoder equipment 11 waits for the end time t_(e) ofthe current program, and then in a step 608, the decoder equipment 11sends the audio playback equipment 15 an order for a new audio profilethat is to be applied.

In step 609, the decoder equipment 11 determines the end time t_(n) ofthe next program from the incoming metadata.

In a step 610, the decoder equipment 11 compares the time t_(p) forecastfor the next change of profile with the end time t_(n) of the nextprogram. If the time t_(p) forecast for the next change of profile isearlier than the end time t_(n) of the next program, then the decoderequipment 11 continues with a step 611, otherwise the decoder equipment11 continues with a step 612.

In step 611, the decoder equipment 11 compares the time t_(p) forecastfor the next change of profile with the end time t_(e) of the currentprogram increased by a fixed time interval Δ (by way of example, thetime interval Δ is taken to be equal to 5 minutes). If the time t_(p)forecast for the change of profile is earlier than the increased endtime t_(e)+Δ of the current program, then the decoder equipment 11continues with a step 607, otherwise the decoder equipment continueswith a step 612.

In step 612, the decoder equipment 11 waits for the beginning of thenext program, and then returns to step 602.

There follows a description of a method in accordance with a secondpossibility that enables the time scheduled for changing the audioprofile to be combined with the end times of the current program and ofthe next program.

This second possibility is identical to the first possibility exceptthat the decoder equipment 11 no longer applies a smooth transition. Inthis second possibility, once the time t_(p) forecast for the nextchange of profile has been reached in step 605, the decoder equipment 11continues with step 608 and sends the audio playback equipment 15 anorder for a new audio profile.

With reference to FIG. 7, there follows a description of a thirdpossibility for the method that enables the time scheduled for changingthe audio profile to be combined with the end times of the currentprogram and of the next program.

In this third possibility, the decoder equipment 11 always causes thechange of profile to coincide with the nearest program transition.

Thus, in step 603, if the time t_(p) forecast for the next change ofprofile is earlier than the end time t_(e) of the current program, thedecoder equipment 11 continues with step 607 and waits for the end ofthe current program in order to send the new profile order to the audioplayback equipment 15.

Likewise, in a step 611 ^(bis), the decoder equipment 11 compares thetime t_(p) forecast for the next change of profile both with the endtime t_(e) of the current program and also with the end time t_(n) ofthe next program, and then if the time t_(p) forecast for the nextchange of profile is closer to the end time t_(e) of the current program(t_(p)−t_(e)<t_(n)−t_(p)) then the decoder equipment 11 continues withstep 607, otherwise the decoder equipment 11 continues with step 612.

There follows a description of a fourth possibility for the method ofcombining the time scheduled for changing the audio profile with the endtimes of the current program and of the next program.

This fourth possibility is identical to the third possibility exceptthat in step 608, the decoder equipment 11 makes a smooth transition tothe new profile, i.e. in addition to always causing the change ofprofile to coincide with the nearest program transition, the decoderequipment 11 also always applies a transition that is smooth.

Naturally this possibility of always applying a transition that issmooth can also be implemented in the first above-described possibility.The decoder 11 can thus make a smooth transition to the new profile instep 608 of FIG. 6, i.e. in addition to always causing the change ofprofile to coincide with the nearest program transition, the decoderequipment 11 also always applies a transition that is smooth.

Advantageously, this transition is of a duration that is shorter thanthe transition performed in the first possibility. For example, in step608, the decoder equipment 11 makes a smooth transition having aduration of about one second, while in the first possibility, thedecoder 11 makes a smooth transition having a duration of several tensof seconds. For example, in step 608, the decoder equipment 11 makes asmooth transition having a duration of one second, while in the firstpossibility, the decoder equipment 11 makes a smooth transition having aduration of thirty seconds.

The description above relates to a second option for an installation anda method of enabling the audio signal played back by the audio playbackequipment to be adapted to the time of content type program being playedback.

In a third option, it is possible to combine the first twoabove-described options.

In particular, it is possible to adapt the audio signal transcribed bythe audio playback equipment 15 from the content type descriptor (as inthe first option) and also to change from one audio profile to anothervia a transition that is smooth (as in the second option).

In addition, it is possible to adapt the audio signal transcribed by theaudio playback equipment 15 both from the content type descriptor (as inthe first option) and also from the time (as in the second option) bycombining the corresponding sets of parameters. As mentioned above,combining two audio profiles is described below.

Whatever the intended option (content type descriptor and/or time), thedecoder equipment 11 is configured, were so desired, to be capable ofmaking a smooth transition when passing from a first audio profile to asecond audio profile.

For this purpose, and in a first implementation, the decoder equipment11 determines a start of transition instant t_(ts) and an end oftransition instant t_(te). For example, the decoder equipment 11determines a transition instant t_(t), and the start and end oftransition instants are calculated to be on either side of thetransition instant t_(t): t_(ts)=t_(t)−d_(t)/2 and t_(te)=t_(t)+d_(t)/2with d_(t) being a fixed duration. For example, d_(t) is equal to 30seconds if a normal smooth transition is intended and to 1 second if ashort smooth transition is intended. The transition instant t_(t) maycorrespond to the end time t_(e) of the current program, to the timet_(p) forecast for the change of profile, . . . . By way of example, thetransition instant t_(t) may be determined as explained with referenceto the second option. Otherwise, it is the start of transition instantt_(ts) that is determined, and the end of transition instant t_(te) iscalculated as being equal to t_(ts)+d_(t). Alternatively, it is the endof transition instant t_(te) that is determined and the start oftransition instant t_(ts) is calculated as being equal to t_(te)−d_(t).

The decoder equipment 11 thus sends an order to the audio playbackequipment 15 to apply the new profile, which order also includes thestart and end of transition instants t_(ts) and t_(te). FIG. 8 gives anexample of an order sent by the decoder equipment to the audio playbackequipment 15 (by way of nonlimiting example, this order is written usingthe JSON-RPC protocol), the order containing simultaneously anidentifier of a new audio profile, parameters of said new audio profile,and the start and end of transition instants t_(ts) and t_(te).

For any instant t lying in the range t_(ts) to t_(te), the audioplayback equipment 15 then calculates a combination coefficientα=(t−t_(ts))/(t_(te)−t_(ts)) and it combines the parameters of the oldaudio profile and of the new audio profile using this combinationcoefficient. As mentioned above, the way in which the installationcombines two sets of parameters is described below.

In a second implementation, it is the audio playback equipment 15 thatcalculates the start of transition instant t_(ts) and the end oftransition instant t_(te). For this purpose, the order for the new audioprofile that is to be applied as sent by the decoder equipment 11 alsoincludes a transition duration.

The audio playback equipment 15 uses the instant at which it receivesthe order as the start of transition instant t_(ts) and it calculatesthe end of transition instant t_(te) from said start of transitioninstant t_(ts) and the received transition duration.

In a third implementation, it is the decoder equipment 11 that itselfcalculates the combination coefficient α and regularly sends orders tothe audio playback equipment 15, which orders include this coefficientas the transition is progressing.

In a fourth implementation, it is the decoder equipment 11 itself thatcombines the audio profiles and it regularly sends orders to the audioplayback equipment 15, which orders include the parameters as combinedprogressively as the transition is progressing.

Whatever the intended option (content type descriptor and/or time), thedecoder equipment 11 is configured, if so desired, to be capable ofcombining two audio profiles. There follows a description of variousalternatives that the installation can perform in order to combine twoaudio profiles. It should be understood that combination may take placein the decoder equipment 11 or in the audio playback equipment 15.

In a first alternative, the installation performs a simple combination.

The installation combines two sets of parameters, each associated with arespective audio profile, in order to obtain a single set of parametersthat are to be applied. For example, the two sets of parameters may befirstly the set of parameters of the order sent by the decoder equipment11 to the audio playback equipment 15 as shown in FIG. 5 and secondly aset of parameters extracted from a table in the memory of the playbackequipment as shown in FIG. 4 b.

In order to combine the two sets of parameters, the audio playbackequipment 15 acts, for each parameter, by looking at the value comingfrom the first set and the value coming from the second set, and as afunction of said two values, it constructs a combined value that is tobe applied:

-   -   if one of the two sets of parameters does not contain a value        for any one of the parameters, then the combined value is the        value coming from the other set of parameters;    -   if both of the sets of parameters contain a value for any one of        the parameters, then the combined value depends on the type of        the parameter:        -   some parameters are gain levels or volume levels. By way of            example, this applies to a gain or to a filter level. For            these parameters:            -   in a first implementation, the combined value is the                smaller or the larger of the values for this parameter                coming from the two sets of parameters as expressed in                decibels;            -   in a second implementation, the combined value is the                average of the values for this parameter coming from the                two sets of parameters expressed in decibels;            -   in a third implementation, the combined value is the sum                of the values for this parameter coming from the two                sets of parameters expressed in decibels. This third                implementation is particularly adapted for gains, but it                is less well adapted for levels.        -   Some parameters are durations. This applies for example to a            reverberation duration. For these parameters:            -   in a first implementation, the combined value is the                smaller or the larger of the values for this parameter                coming from the two sets of parameters;            -   in a second implementation, the combined value is the                average of the values for this parameter coming from the                two sets of parameters;        -   Some parameters are Boolean values. This applies for example            when determining whether a filter is to be on or off. For            these parameters:            -   if both sets of parameters have the same value, then the                combined value is equal to that same value;            -   if both sets of parameters have different values, then:                -   in a first implementation, the combined value is                    equal to the “true” logic value;                -   in a second implementation, the combined value is                    equal to the “false” logic value;                -   in a third implementation, the element (e.g. the                    filter) controlled by the value of the Boolean                    parameter is also associated with a secondary                    parameter that affects the magnitude of its effect.                    By way of example, this applies to the “level”                    parameter for a reverberation filter. Under such                    circumstances, the combined value of the Boolean                    parameter is equal to the “true” logic value, and                    the combined value of the associated secondary                    parameter has its value reduced (relative to the                    value of the non-combined associated secondary                    parameter). For example, the combined value of the                    “level” secondary parameter is equal to the value of                    the “level” secondary parameter in the set of                    parameters for which the “filter” parameter is                    “true” minus a predetermined fixed value (e.g. 3                    dB).    -   Otherwise, or in addition, if both sets of parameters contain        values for any one of the parameters, then the combined value is        determined in compliance with the second alternative as        described below while using a predetermined value for the        correlation coefficient α, for example 0.5.

In a second alternative, the installation performs weighted combination.

The installation combines two sets of parameters, each associated with arespective audio profile in order to obtain a single set of parametersthat are to be applied in compliance with a variable combinationcoefficient α. By way of example, the two sets of parameters may be thesets for the start and the end of a smooth transition, and thecombination coefficient α is representative of progress through thetransition such that α=0 at the beginning of the transition and α=1 atthe end of the transition.

With reference to FIG. 9, in a first implementation, the audio signalreceived by the audio playback equipment 15 is copied, and each copy isprocessed independently with a respective one of the two sets ofparameters by respective processes 81 and 82. Thereafter, the twoprocessed copies s₁ and s₂ are combined by an average that is weightedby the combination coefficient α in order to obtain a modified audiosignal s_(o) that is to be played back: s_(o)=(1−α)×s₁+α×s₂.

It should be observed that this first implementation is equallyapplicable regardless of whether the processes 81 and 82 comprisedifferent processes or the processes 81 and 82 are identical.Furthermore, this implementation can be used even if one of theprocesses 81 or 82 does not modify the audio signal received by theaudio playback equipment 15, with this making it possible, for example,to activate or deactivate a parameter and thus a sound effect in smoothmanner.

The first implementation thus proposes combining two sets of parametersby processing said sets independently.

This first implementation presents the advantage of being generic: itcan be applied to any pair of processes 81 and 82. In contrast, thisfirst implementation is relatively expensive in terms of calculationsince it requires the audio signal that is received by the audioplayback equipment 15 to be processed twice over.

In a second implementation, the parameters of the two sets are combinedindependently in pairs in order to obtain a set of combined parameters,which set is then applied once only to the audio signal that is receivedby the audio playback equipment 15.

In a second implementation:

-   -   Certain parameters have numerical values. These parameters are        combined by an average that is weighted by the combination        coefficient α.    -   Certain parameters are Boolean values, e.g. defining whether a        filter is or is not to be applied. For these parameters:        -   if both sets of parameters have the same value, then the            combined value is equal to that same value;        -   if both sets of parameters have different values, then one            of the sets of parameters, referred to as the “active” set            of parameters contains the value “true” and the other set of            parameters, referred to as the “inactive” set of parameters,            contains the value “false”. Under such circumstances, the            combined parameter takes the “true” value. In addition:            -   In a first option, the other secondary parameters of the                element controlled by said Boolean parameter are                combined by taking the values of the active set of                parameters and by imposing predetermined minimum values                as values for the inactive set of parameters (and not                the real values of said inactive set of parameters). For                example, if the Boolean parameter controls activation of                a filter, the level secondary parameter of the filter of                the inactive set of parameters is taken as having a                value of −60 dB and the application duration secondary                parameter of the filter of the inactive set of                parameters is taken as having a value of zero.            -   In a second option, the elements controlled by said                Boolean parameter includes a secondary parameter that                affects the magnitude of its effect. Under such                circumstances, said parameter is combined by taking the                value of the active set of parameters and by imposing a                predetermined minimum value as the value for the                inactive set of parameters (and not its real value). The                other parameters of said element take values equal to                the corresponding values of the active set of                parameters. For example, if the Boolean parameter                controls activation of a filter, the level secondary                parameter of the filter of the inactive set of                parameters is taken to have a value of −60 dB. In                contrast, the combined value of the application duration                secondary parameter of the filter is taken to be equal                to the value of the application duration secondary                parameter of the filter in the active set of parameters.

A third implementation is described below that combines the twoimplementations described above. This third implementation thus proposesa hybrid combination of two sets of parameters.

In this third implementation, certain parameters are thus combinedindependently in pairs in order to obtain a partial set of combinedparameters suitable for application once only to the audio signalreceived by the audio playback equipment (as in the secondimplementation), and other parameters are combined by independentprocessing (as in the first implementation).

For example, and with reference to FIG. 10, the equalization parametersmay be combined to be applied to the signal once only by a process 91,while the parameters of a filter, such as a reverberation filter, areapplied to the signal by independent processes 92 and 93 (via copies ofthe signal) and they are combined a posteriori.

Naturally, the invention is not limited to the embodiment describedabove, and variant embodiments may be provided without going beyond theambit of the invention as defined by the claims.

Thus, although above, the decoder equipment is a decoder box, thedecoder equipment could be any other equipment capable of formingaudio/video decoding, and for example it could be a games console, acomputer, a smart TV, a digital tablet, a mobile telephone, a digitaltelevision decoder, a set-top box, etc.

Although above the video playback equipment is audio/video playbackequipment, it could be any other type of video playback equipment, suchas a television set, a video projector, a tablet, a mobile telephone,etc. The video equipment and the decoder equipment could thus togetherform a single entity.

Likewise, although above the audio playback equipment is an externalconnected loudspeaker, it could be any other equipment having aloudspeaker, e.g. a sound bar. Nevertheless, the audio equipment shouldnever be incorporated in the decoder equipment.

The numbers of video playback elements and/or of audio playback elementsand/or of decoder elements could be greater than in the descriptionabove.

Although above the audio/video stream and the metadata are contained inthe same incoming multimedia stream, the audio/video stream and themetadata could be contained in two different incoming streams sent inparallel to the decoder equipment. Thus, in a nonlimiting option, if thebroadcast network is an Internet source supplying an audio/video streamusing a DASH protocol (e.g. as described in the standard ISO/IEC23009-1,“Dynamic adaptive streaming over HTTP (DASH)), the metadata could beincluded in a corresponding MPD manifest (e.g. an MPD manifest asdescribed in section 5.7 of said standard ISO/IEC23009-1).

The audio profile could be defined by some number of parametersdifferent from those described above and/or by different parameters.

In the absence of metadata, or if the metadata does not includeinformation about the program being viewed, the installation could beconfigured to apply a default audio profile that is predefined in theaudio playback equipment.

1. Decoder equipment comprising: a first output suitable for connectingto audio playback equipment; a second output suitable for connecting tovideo playback equipment; a communication interface arranged in serviceto receive both an incoming audio/video stream and also incomingmetadata; processor means arranged: to process the incoming audio/videostream in order to supply an audio signal at least to the audio playbackequipment and a video signal to the video playback equipment; to extractfrom the incoming metadata information about the incoming audio/videostream and consequently to generate an order for the audio playbackequipment, the order specifying an audio profile that is to be appliedas a function of said information; wherein the information comprises atime.
 2. The decoder equipment according to claim 1, wherein theinformation is an end time of a program contained in the incomingaudio/video stream and played back in service by the audio playbackequipment and by the video playback equipment.
 3. The decoder equipmentaccording to claim 2, wherein the processor means also extract, from theincoming metadata, additional information comprising an end time of aprogram that is contained in the incoming audio/video stream and that isgoing to be played back in service by the audio playback equipment andby the video playback equipment after the program currently being playedback by the audio playback equipment and by the video playbackequipment.
 4. The decoder equipment according to claim 1, configured tocause an audio profile change to coincide with a program change.
 5. Thedecoder equipment according to claim 1, wherein the processor means alsoextract from the incoming metadata other additional informationcomprising a content type descriptor of the incoming audio/video stream.6. The equipment according to claim 5, wherein the processor meansinclude at least one table associating each descriptor with parametersdefining an audio profile, at least in part.
 7. The decoder equipmentaccording to claim 5, wherein the processor means include at least onetable associating each descriptor with an audio profile identifier. 8.The decoder equipment according to claim 1, wherein the audio profile isdefined at least by a parameter for equalizing the audio signal.
 9. Thedecoder equipment according to claim 1, wherein the audio profile isdefined at least by a compressor or limiter effect.
 10. The decoderequipment according to claim 1, wherein the audio profile is also afunction of the time at which the audio/video stream is played back. 11.The decoder equipment according to claim 1, configured to calculate atransition period between two audio profiles.
 12. The decoder equipmentaccording to claim 1, configured to order the audio playback equipmentto calculate a transition period between two audio profiles.
 13. Thedecoder equipment according to claim 11, wherein the transition betweentwo profiles is caused by a change of time at which the audio/videostream is to be played back and/or a change of program contained in theincoming audio/video stream that is played back in service by the audioplayback equipment and by the video playback equipment.
 14. The decoderequipment according to claim 1, configured to combine two audioprofiles.
 15. The decoder equipment according to claim 1, configured toorder the audio playback equipment to combine two audio profiles. 16.Audio playback equipment including a communication interface arranged inservice to receive from decoder equipment both an audio signal and alsoan order for an audio profile that is to be applied, the audio playbackequipment including processor means for adapting the audio signal as afunction of said order.
 17. The audio playback equipment according toclaim 16, wherein the processor means include at least one tableassociating audio profile identifiers with parameters defining an audioprofile, at least in part.
 18. The audio playback equipment according toclaim 16, configured to change audio profile at a given time specifiedby the decoder equipment.
 19. The audio playback equipment according toclaim 16, configured to ensure a transition period between two audioprofiles.
 20. The audio playback equipment according to claim 16,configured to combine two audio profiles.
 21. The audio playbackequipment according to claim 20, wherein for at least one audioparameter, the audio playback equipment duplicates the audio signal itreceives in service from the decoder equipment, applies respective audioparameters to each copy, and combines the two copies in order to obtaina combined audio signal.
 22. The audio playback equipment according toclaim 16, wherein for at least one audio parameter, in service, theaudio playback equipment applies a combined audio parameter directly tothe audio signal received from the decoder equipment.
 23. Aninstallation comprising both decoder equipment according to claim 1, andan audio playback equipment including a communication interface arrangedin service to receive from decoder equipment both an audio signal andalso an order for an audio profile that is to be applied, the audioplayback equipment including processor means for adapting the audiosignal as a function of said order.
 24. A method of generating an orderfor an audio profile that is to be applied by audio playback equipment,the method being performed by the decoder equipment according toclaim
 1. 25. A method of applying an audio profile, which method isperformed by the audio playback equipment according to claim
 16. 26. Acomputer program including instructions for causing the decoderequipment according to claim 1, to execute steps of a method ofgenerating an order for an audio profile that is to be applied by audioplayback equipment.
 27. The computer program including instructions forcausing the audio playback equipment according to claim 16, to executesteps of a method of generating an order for an audio profile that is tobe applied by audio playback equipment.
 28. A computer readable storagemedium storing the computer program according to claim
 26. 29. Thecomputer readable storage medium storing the computer program accordingto claim 27.